The paper-making industry is a universally traditional industry. The development of the paper-making industry is the index of the economy and living standard for a country. The source of paper pulp mostly comes from woods. (It needs four metric tons of wood to produce one metric ton of paper pulp. This means cutting down twenty-three trees.) Because of that, the forest area on the earth has been and is rapidly decreasing. The ecological balance problem becomes more and more serious. Furthermore, a great quantity of water and chemicals are needed to wash pulp. However, waste liquid from the wash is discharged from a factory in the traditional chemical paper-making process. This also results in environmental pollution. The rivers and oceans are polluted. Nowadays, people in the whole world pay much attention to environmental protection. Corporations in the paper-making industry are obliged to spend money to improve environmental quality. The paper production costs are thus raised. Those problems really strike against the paper-making industry.
The annual yield of rice straws is about 2300 thousand metric tons in Taiwan. The organic components of rice straws are almost more than 95%. The organic components include 41.3% carbon, 0.81% hydrogen, 20.6% hemicellulose, 24.7% cellulose and 7.7% lignin. Conventionally, the handling methods for rice straws include manufacturing them into straw ropes, straw bags, straw mats and cardboards, serving them as covering materials for a plot of land, utilizing them as fuel, and mixing them with other material to produce a compost. Also, rice straw could be directly buried in soil or burned for recyclably using the nutrition. Nowadays, the rice straws are rarely used as fuel, feed, straw bags or straw mats because of the expensive costs and advanced science and technology. Most of the rice straws are locally burned or directly buried in soil, which often result in environmental pollution. On the other hand, since the rice straws are rich in fiber, it will be very helpful to mitigate the environmental pressure of logging the trees for papermaking if the non-woody fiber plants could be well developed and used. In the past, the fiber production methods using non-woody fiber plants as original material were generally chemical or semi-chemical methods. However, there exists three difficult problems in the paper-making industry resulting from the chemical production method for pulp. They are described as follows. (1) Large amounts of silicates and black liquid with high viscosity produced in the process often result in serious problems in recycle systems. (2) The deposition of calcium carbonate will be affected by the silicates and thus will lead to the dirt appearance attached on the vapor apparatus. In addition, the evaporator piping gets undesirable black viscous liquid attached thereon. Therefore, it needs to be shut down for cleaning. (3) The unstable status of the steamer and boiling machines waste the fuel and thus raise the production costs.
Biotechnology is the key for reorganizing the traditional industry structure. It is very important for the papermaking industry to move towards the use of the biotechnology for papermaking. The advantages of using biotechnology for papermaking are the reduction of production cost, the improvement of pulp quality and the safety maintenance of the working environment, etc. There are many methods and products produced, for example, the removal of gum or printing ink by using enzymes, paper bleaching by using xylanase or lignin oxidizing enzyme, and the improvement of pulp viscosity by using enzymes (non-woody fiber pulp especially). However, these methods also have the drawbacks of environmental pollution caused by waste liquid and energy consumption. Therefore, it is imperative to seek the assistance of biotechnology for solving and overcoming the drawbacks of papermaking by using chemical methods.
Researchers in many countries of Europe and America attempt to use white-rot fungi, such as Phanerochaete chrysosporium and Cereporiopsis subvermispora, grown on wood slices for removing the lignin of woods and saving the cost and energy of paper making. Although there are some positive results from those methods, it takes too much time for the industry to grow the white-rot fungi on woods outdoors.
The main purpose of the present invention is to apply the decomposition abilities of microorganisms for decomposing organic matter in the papermaking processes of waste straws so as to establish a model of biopulping processes for non-woody fiber plants. The non-woody fiber plants will become an important source of the raw materials of paper pulp. This approach can decrease the consumption of forest resources and the production of chemical wastes. The existing problems of papermaking are solved.
From the above description, developing a new pulping method with the advantages of low production costs, low or non pollution has become a major problem to be solved. In order to overcome the drawbacks in the prior art, a biopulp for non-woody fiber plants and a biopulping method thereof is provided. The particular design of the present invention not only solves the problem described above, but also uses the waste rice straws and a biopulping method to produce paper pulp for paper-making. It does not need to use the chemical or semi-chemical method, and therefore no pollution problems exist.
Therefore, the present invention provides a biopulp for non-woody fiber plants and a biopulping method thereof which overcomes the disadvantages described above.